Employees return to work at UPS warehouse in San Francisco
UPS trucks are rolling again at a warehouse in San Francisco where an employee shot and killed three colleagues and wounded two others.
Workers returned to the facility Thursday, a day after the shooting led police to evacuate the warehouse.
Police say the three UPS drivers were killed by 38-year-old Jimmy Lam, who fatally shot himself in the head in front of officers.
A motive in the killings has not been determined, but a union official has said Lam filed a grievance over what he considered excessive overtime.